This relates generally to image sensors and, more particularly, to image sensors with avalanche photodiodes.
Image sensors are commonly used in electronic devices such as cellular telephones, cameras, and computers to capture images. In a typical arrangement, an electronic device is provided with an array of image pixels arranged in pixel rows and pixel columns. Each pixel includes a photodiode that receives incident photons (light) and converts the photons into electrical signals. In some scenarios, the photodiode is an avalanche photodiode capable of converting relatively small numbers of photons into a measureable charge. However, avalanche photodiodes are particularly susceptible to thermal effects which can generate dark current and noise in the corresponding image.
It would therefore be desirable to be able to provide improved image sensors with avalanche photodiodes.